Like a lot of folks on the Peninsula, Brian Howell is concerned about the environment. So, when Howell’s Acura Integra died last January, he started shopping for a Toyota Prius.

But Howell, who has degrees in physics, mathematics, material science and engineering, found the Prius a disappointment. He said he wanted a car that didn’t rely on the petroleum that sets U.S. policy and spurs international wars; he wanted to be free of the carbon dioxide bringing our planet toward climate catastrophe. What he wanted, he said, was an electric car.

When Howell couldn’t find one, he purchased an electric bicycle and began commuting 7 miles from his home in Belmont to his job as a Sony engineer in Foster City.

Now, he’s a convert.

“I was always planning on buying a car, but I was addicted to these (electric) bikes,” said Howell. “They’re easy to operate. They allow you the convenience of a motorcycle. They give you exercise and fresh air. It has radically changed my life.”

Last year, as gas prices soared, congestion worsened and concern for the environment heated to a fever pitch, more commuters began to leave behind their cars. Sure, many have wisened up to public transportation, but some were wooed by light electric vehicles — a broad range of contraptions that don’t putt-putt-putt so much as zoom-whir-zoom. The LEV field is broad, including scooters, pedicabs, Vespa-like motor scooters and even miniature cars.

For many, electric bikes are the gateway into the world of LEVs — but why is the two-wheeler so popular?

Rob Means, the founder of Electro Ride Bikes & Scooter in Milpitas, has a simple explanation.

“More smiles per mile,” he said.

Means, who sells a wide selection of the electric bikes and do-it-yourself kits out of his South Bay home, said that electric bike sales are increasing because it’s a safe way for fed-up commuters to test the electric waters without risking too much money.

Bicycles, he said, are familiar, easy to use and “if you run out of juice, you just pedal home.”

The benefits of an electric bike, said Means, are economic, environmental and health-related. Despite its high sticker price (the models he sells range from $800 to $1,500), that’s nothing compared to the yearly cost of owning an automobile ($7,834, according to AAA). Naturally, less money spent on fuel means less carbon dioxide and nitrogen dioxide to harm the air quality, and the health benefits of exercise are self-evident.

The persuasive arguments, coupled with technology advances, have driven multiple manufacturers into the business — at least 30, said Means. Small manufacturers sell boutique bikes for $5,000 and more, and big-box retailers peddle models for as low as $300 — although Means refers dubiously to the latter as “landfill material.”

Most electric bikes weigh between 60 and 90 pounds and come equipped with an electric motor, a battery, a charger and a speed controller (throttle- or pedal-activated). The motors, ranging from 250 to 1,500 watts, are affixed to the front or back wheel. The batteries, predominantly 24- or 36-volt lead-acid or nickel-metal-hydride, tend toward the size of a bread basket.

Riding an electric bike is practically effortless. Throttle-driven models can be powered by one’s thumb, but a little effort on the rider’s part is encouraged to spare battery life and increase speed. Pedal-powered models activate the motor by pedaling alone.

Perhaps the electric bike’s biggest impediment is the batteries, whose 20-pound heft and limited 8-10 mile capacity may turn consumers off. However, the spread of lithium batteries, which weigh four times less and extend the life of the battery some 25 percent, promises further evolution and higher sales to come.

In fact, Howell, the engineer at Sony, has partnered with Means to retail an electric bike of his own design — a recumbent which he claims can reach speeds of more than 30 mph and exceed distances of 100 miles. Not bad, considering an average electric bike reaches speeds of about 25 mph, requiring a charge after every 8-10 miles.

Of course, electric bicycles are limited by law to traveling less than 20 mph, but Means insists that “nine out of 10 (cops) don’t know the rules of an electric bike.”

A compelling feature of the bikes, Means said, is that they remove the three most frustrating parts of riding a plain old bicycle: starting from a stop, going up a hill or battling a strong wind. And although hard-core cyclists may sneer, charging that electric cyclists are cheaters, Means has a ready reply to the charge.

“I just generally remind them that they are thinking from the paradigm that a bicycle is for exercise, not recreation,” he said. “For those of us who think of it as transportation, it’s not a cheat.”

Leafgren, who studies industrial design at San Francisco State University, already knew a great deal about LEVs, but he wasn’t ready to ditch one of the two family cars. In spite of the $40 a week in gas, the traffic back-ups, the hassle of looking for a parking space and getting ticketed anyway, Leafgren wasn’t ready to say goodbye to his car. Then, in January, the Bay Bridge tolls climbed to $4.

“It’s the least of the reasons, but it’s the straw that broke the camel’s back,” said Leafgren.

Now Leafgren wanted to buy a $600 kit to convert a used mountain bike into a whirring, pedal-assisted commuting machine. Sure, he had concerns about relying on an electric bike, but he was excited for a little exercise and fresh air, and tired of “feeling crappy about global warming and contributing to oil dependence.”

“This may be your first electric vehicle,” Means told Leafgren. “But I can guarantee it ain’t gonna be your last.”

A couple of days later, Means said, Leafgren bought the kit. Then, on the same day, he sold his car.

“We live in a car culture,” said Means. “But I’m starting to see a shift. We haven’t gotten up the hill, but the curve is starting to bend.”